So, I'm an absolute noob around these parts, but I thought I'd get stuck right in and tout about for collaborators.

Being a bit of a writer, I've got a mountain of old game-world ideas knocking about, and discovering this most excellent of forums leads me to think it might be worth having a go at developing one as an indie game.

The idea I chosen is one I've given the working title "Sentinel". It would be a single-player open-world FPS with heavy RPG elements.

Premise:
Just under 200 years ago, the Colonial Development Foundation set out from a decaying Earth to colonise the planet Pangyrea. The expedition ended in catastrophe; for reasons which remain unknown, the colonial fleet was heavily damaged, and went down hard, losing most of the resources and assets which would have been key to a smooth, rapid colonisation process. Today, the descendants of those who survived this disaster struggle to survive on a hostile world, living out of disconnected and isolated towns scattered around a stretch of Pangyrea's equatorial region.

The player takes the role of a young person from the town of Nuolund, sent out on a rite of passage as they come of age. Tasked with venturing deep into the wreck of the Tyger to search for viable tech or undiscovered cultural remnants, they discover an artefact called a CVA (Cybernetic Virtual Adjutant), a remnant of the Colonial Sentinel Service, the colonial fleet's elite protectors. Confronted with mysterious, well-armed soldiers with advanced weapons, the player is helped to escape by the CVA's Mind, Dyna, and offered a glimpse at the reality behind the fleet disaster: a massive attack by a superior force.

Returning home, the player gains a mission: uncover the realities behind attack which doomed the original CDF mission, and gather allies to combat a resurgent old enemy.

Behind the scenes:
In the years after the CDF fleet departed Earth, a military junta rose to power out of Mexico, gained dominion over much of the Americas, and had a stab at outright world domination. Using advances in FTL made since the CDF first fled the planet, it sent out probes to establish the CDF's destination at higher speed than the CDF fleet was travelling, aiming to figure out whether a CDF-colonised Pangyrea might be a future threat. By chance, a probe landed on milennia-old alien ruins, the remnants of an advanced civilisation which had destroyed itself. The junta immediately built and dispatched a warship to Pangyrea, more than a match alone for the whole CDF fleet; only a suicide run by the Odyssey, under the command of CDF CEO and original inventor of FTL Barsten Kovic, prevented outright genocide in the orbital battle that followed. By the time that the survivors of the fleet were out of stasis, anyone (human or Mind) who really knew what had just happened was dead, and basic survival was the top priority.

Back on Earth, defeating the junta took the combined effort of a global alliance, and left the planet in one hell of a mess. Now, a junta has emerged, revering the legacy of the original, and likewise seeking to gain control of both Earth and Pangyrea.

The landscape:
The Pangyrean environment is mostly jungle and savannah, puntuated by a mountain range and a cluster of lakes. The 12 towns embody varying tech levels of architectural styles; mutual isolation, scarcity, mistrust, and occasional politiking mean that available science and technology ranges from Iron Age equivalence to late 20th-century equipment.

Even those towns which have access to data and schematics dating from the original colonial mission don't have the resources to manufacture advanced gear; highly dangerous local wildlife, outcasts and tribalistic raiders make the reason too hazardous to survey and mine the landscape for the necessary materials. Only Ariopolis, an enigmatic town set by a high-altitude lake, has much advanced technology, and it's notoriously reticent about sharing.

All that means that there's scope to play around with a lot of artistic and design ideas and integrate different visual concepts into the gameplay.

What's needed:
Everything.

Seriously, if you like the sound of this scenario and fancy pitching in, pipe up and comment. Whether that's art, code, engine build, additional writing, support functions, whatever. I'd like to make this a goer and I'm happy to hear from anyone who has a yen to get into building a new game from the bottom up.

I figure that there's scope to create a 'virtual studio' and launch a funding appeal on Kickstater as Sentinel starts to take shape. Maybe we even get lucky, and we can start to turn this into a serious release with external backing.

There's more content than the above already developed, of course; I'm happy to circulate anything as needed, and create a "world bible" as we go. For example, so far I've got a clear idea of the game mechanics (including how the CVA should work), an outline plot, names and backgrounds for each of the 12 towns, and some ideas on enemies and allies. I even what the are-they-dead-or-are-they-still-alive aliens would look and behave like (textually, not visually!), thought I'm in two minds about whether to let them stay extinct.

To be clear, I've not able to pay anyone for first-stage involvement, of course.

ambershee wrote: Your problem is that this is not a description of a game, in fact there's no mention of a game at all. What you have here is a story.

As a result, why would a game developer want to get on board at all?

While that's true, I find it a bit unfair. It wouldn't be too hard to come up with a genre (FPS or RPG) and gameplay mechanics for this game from reading the story. I read it and thought: "hey, at least someone actually writes a story that makes some sense and is structured." It's a bit generic, but still could turn out well enough when the action is right. The problem I see is much more with ambition.

It's nearly impossible to create a project (even a prototype) like this from scratch and without deep knowledge of how to produce games. I recommend to Vitrovius to read a few books on game design and possibly start working out features he wants in the game; and then produce a very small prototype of it, for crowd funding. A high concept would also entail an animatic of a cutscene. Doesn't have to be polished or anything animated; just use After Effects.

I'm currently reading: Michael E. Moore, Basics of Game Design. And I take a lot from it. Pretty good to look into if you don't have much of an idea about development; and even if you have - it can't harm.

General stuff:
I pretty much agree with what SinKing wrote. Nowadays reading about Game Design and start a crowd funding campaign is one way of starting such a project. Another one would be approaching it with a mod mentality. In other words:
Build a team that's working on it for free as if it was a mod. People do that for fun, in order to gain experience, to further enhance their skills, produce additional content for the portfolios or to get their names out there. Later you would go with crowd funding to get the money for publishing and/or software licences.
There is no better way. Both are equally hard, because game development is. Seriously, you're gonna spend a lot of hours, pobably over the course of many years. Starting is easy...

Either way you need to have something to show the people. No skilled developer will join a project with no actual content unless it's by some known developer.

As already pointed out, you can read books that specifically deal with Game Design, but (as with all books) I don't recommend blindly following them since there is no universal guide to the perfect piece of art. Always question the norm. Not in a hipster kind of way, but if a book tells you that "this is a good idea", ask the question "Why?". People who just accept what they hear/read are just scratching the surface. Those who question, really show interest and will end up at the core of the matter.

Another way would be analyzing games that are good (games you really enjoyed and were a critical success). This is not the same as just playing those games and it's not something everyone can do. I as computer science student have this ability. It's pretty much part of the skillset I need to have.
Abstraction is the keyword. Breaking problems that cannot be solved on their own down into small problems that you can actually solve.
"Why is the Half-Life series known for having excellent game design?"
"What makes Amnesia so damn scary?"
And so on.

Your idea:
First, an idea isn't worth a damn. It may sound harsh, but it's not meant offensive. The thing is that producing ideas isn't anything special. Everyone can provide ideas for a couple of games within 5 minutes. Besides that there aren't many stupid ideas, because often it's more about how they're executed. Here's one example:
"A shooter about a team of US soldiers go to the arabs, because there was a natural disaster and the arabs failed to safe themseles. Now you must rescue the survivors."
This might sound like the plot to yet another generic pro-military/USA shooter, but it's also the plot of Spec Ops: The Line which is renowned for its story.

You mostly provided a story, a setting. That's not much, but it's fleshed out rather well and by far not every idea posted here is.
The story is nothing special at first glance. Space ship flies to other planet for colonialisation, shit happens, because of course it does. Rest of the people have to survive. It's not a bad one though. I think it boils down to how much backstory you provide, whether you make interesting characters and how you actually tell it.

As mentioned before, this is not, specifically, a game idea. This is solely a story. Why not simply write a book? More importantly, why would a programmer/artist work on this idea over theirs? What are you offering that they do not have?

I think ("think", that's no rule) that a writer should always have a second profession in indie game development. The thing is that as a writer you don't produce content but context. You can't really show this context to others in order to build a team and get people interested. You need something more. Even more so if you are the one who actually starts a project.

If you really want to make this a game, start thinking about the game itself. What about the gameplay, the mechanics? Right now all you have provided in this regard is "It would be a single-player open-world FPS with heavy RPG elements."
Start thinking about the details, just like you did with the story. Then your project might really actually go somewhere.

Zanza1000 - you're kinda right. To me, the best games these days are basically interactive movies.

I'm definitely ambitious for this concept; maybe too ambitious, but every good game starts with a good idea. To me, the takeaway lesson from developing anything new is that you need a handful of people who have distinct skill-sets who can together make a solid team, willing to put a bit of time and effort into startup in the hope that startup will lead to something more.

And I'm happy to offer an overview of what I have so far in terms of gameplay mechanics, all tied back into how the story if told. This is basically pared-down copy-and paste content from my notes (so apologies in advance if the formatting goes a bit squiffy). I've written much of it from a 'user manual' perspective. You can see where blanks indicate decisions yet to made on content, ergo offering room for further input (noteably on specific weapons).

The CVA

The CVA is a piece of tech originally worn by Colonial
Sentinel Service officers. It is a sentient AI, contained in a rig designed to
enhance the wearer's combat abilities and deep-space survivability by
propagating nanotech into their bloodstream. The nanotech then creates
cybernetic physical structures, including a retinal heads-up display and an
audio module, and provides enhanced healing and counter-toxicology functions.
The CVA device is also able to monitor and analyse equipment and the
environment, and record and store massive amounts of audio and visual data. The
AI in it communicates with the wearer through the structures it creates.

The AI in this particular unit is called Dyna. Dyna's
previous user was a female officer, so her interactions will be different for a
male character and a female character

CVA Modules are driver codes for advanced functions
available in the CVA, and significantly improve your abilities when found. They
work on Code Pathways, so more advanced Modules will not function until you
have the more basic Modules along the same Pathway. You can find Modules in the
wrecks of colonial fleet ships, or by trading for them in villages; although
villagers might not really know what they have, items of hardware containing
Modules are often revered relics, and not cheap to obtain

Healing: nanotech in your bloodstream creates a mild
regenerative effect, meaning that your wounds heal much quicker than normal
and, over time, you can return to full health without medical intervention. Can
be upgraded with multiple regeneration efficacy improvements, and a cybernetic
revivification system (which automatically restarts your heart if you take a
lethal wound, returning you to 10% health; automatically self-recharges;
further upgrades are available for health restoration level and recharge time).

Resistance: cybernetic organs and nanotech provide extra
resistance and survivability against environmental hazards, slightly slowing
the rate at which damage is inflicted by environmental hazards and improving
the time taken to recover from environmental damage. Can be upgraded for
multiple improvements in biotoxicology resistance, radiation resistance, fire
resistance and electrical resistance.

Shock: the CVA's on-board weapons system, initially
deactivated, which creates a cybernetic module in the hand. When active, it can
be used like an equipped weapon to deliver a variable-yield electric shock to
an enemy; at low yields, this stuns an enemy briefly, at high yields it can be
lethal. As the Shocker is powered from a combination of your bioelectricity and
ambient static, it has a long recharge time when its current charge reservoir
is used up. Upgrades are available for shock yield power, recharge time, range
(initially, the Shocker is touch range only), and ability to apply the shock
effect to wielded melee weapons.

In addition to Modules, the player can kind music and video
data records throughout the game world. Visual records help tell the game's
story, and can be viewed through the HUD. The player can also use the HUD to
select music to listen to when acquired; all music in the game is either
proprietary (intended to be indicative of 'future' music) or out-of-copyright
classical or world music. Any music heard in the game world is automatically
recorded by Dyna and can be listened to at any time in the future.

Items, workshops and crafting

Almost all items of equipment you find as you explore the
world can be used as, or salvaged for, Components. The better their condition
and basic type, the better the components you can salvage.

You can use Components at Workshops to craft better
equipment or improve your existing equipment. Some Workshops are better than
others, based on the type and variety of Tools available. You can also collect
or buy Tools to take home to Nuoland with you and improve the Workshop in your
cabin. In the world, you can only use your home Workshop to craft something
completely new; all other Workshops can only be used to upgrade equipment you
currently have.

Types of equipment you can craft include:

Worn items: you can create or improve clothing to provide
better damage resistance, and greater carrying capacity, or to make it more
attractive or frightening to other people.

Weapons: you can create or improve weapons across different
types and tech levels. Weapon customisation can enable a range of improvements.

Useable items: you can create or improve different kinds of
usable Kit, including Medical Kits, Repair Kits, poisons and explosives

Ammo: you can craft a range of different types of ammo for
your weapons, and recharge spent energy cells

All craftable items are based on Specs (Worn Items, Weapons,
most Ammo, some Useable Items) or Recipes (some Useable Items, some Ammo;
primarily poisons and food). These can be found in world by using the CVA to
scan equipment you find to determine its structure and composition. Some Specs
and Recipes can also be bought from stores, or found in computer systems around
the environment. Dyna also begins the game with a limited range of stored
Specs; for narrative purposes, this is based on the preferences of her previous
wearer.

Equipment, Carrying and the Stash

Weapons are divided into Classes. You can only equip 4
weapons at a time, based on only being able to use 4 of the Carrying Equipment
types available for each Class. Each type of Carrying Equipment allows you to
equip and wield a weapon in a corresponding Class, plus access a quantity of
ammo for that weapon. Each item of Carrying Equipment can be improved by at
Workshops, where you can also manufacture Carrying Equipment types you don't
current own. Each of the available types of Carrying Equipment also lets you
carry a quantity of a specific kind of Thrown Weapon, suited to the specific
kinds of weapons you can carry.

Weapon Classes, their corresponding Carrying Equipment type,
include

Pistol: Pistol Belt

Carbine: Light Bandolier

Rifle: Chest Webbing

Support: Gunnery Pack

Long blade: Sword Belt

Light Melee: Sheath

Sniper: Sniper Bandolier

Bow: Quiver

Primitive: Leather Strap

Explosive: Munitions Pouch

Backup*: Backup Holster

*Some small weapons of different Classes can also be used as
a Backup Weapon. These are usually very concealable, too, and won't be found if
you're searched. You can store one of these in a Backup Holster with a small
amount of extra ammo, either as a holdout or to give you an edge in a risky
situation in a village where you would normally be required to leave your
weapons at the gate. When this item of Carrying Equipment is used, you can also
store 1 of any type of Thrown Weapon. You can equip the Backup Carrying Item
with a weapon without effecting your Carrying Equipment limit.

When you have the right kind of Carrying Equipment equipped,
you have the option to swap out a weapon you're carrying for one you find in
the world, as well as stripping found weapons for components.

When you strip a piece of equipment for components in the
world, this leaves you vulnerable, so be careful of potential enemies. Of
course, you can abort at any time. [stripping any item triggers a brief
animation, different for different kinds of item]The CVA can identify which components you can
salvage from any item; your Technician Skill also influences this.

When you have a Weapon of any Class equipped, you can
sometimes switch out some Components without a Workshop, for Special Options.
For example, you can add or remove a Suppressor, switch out different types of
Scope, switch to a special kind of ammo, or swap different kinds of Charger
Core out a directed energy weapon. The number of options available is based on the
capacity of your corresponding Carrying Item.

How much of other kinds of items you can carry is based on
other Worn Items. All Worn Items allow you to carry more or less from a mixture
of each of 4 categories: Useable Items, Components,Cultural Items, Tools. You can map useable
items from these categories to the interface from the appropriate inventory
pane. Useable Items are sub-categorised as Kits, Food, Drink, or Poisons.
Components are sub-categorised as Weapons Components, Wearable Components and
Useable Components. Cultural Items are sub-divided into Art (with a detail view
option), Books (readable), Jewellery, and Miscellaneous. Where an item is
Mission-critical, this is highlighted in the inventory.

The primary kind of Worn Item is your Pack. There are four
different configurations of Pack, each emphasising a different kind of item but
able to carry everything to some extent. Your Pack can also carry extra Ammo
for weapons you're not currently carrying, so you can transport it or sell it.
Each configuration can be upgraded.

Some items stack together within a single slot for their
type, to different levels. This is indicated in the item profile. Conversely,
some very large items take up more than one slot of their type, also indicated
in their profile. For example, you can carry a stack of 10 Steel Fasteners per
Components slot, but Arrows take up 5 Ammo slots.

Specific items of clothing and armour provide bonuses to
capacity for each type.

At your Cabin in Nuoland, you can use the available Stash
capacity to store a plenty of additional gear. For example, when you're not
using an item of Carrying Equipment to equip a weapon of the appropriate Class,
you can store it back at your house in Nuoland.
The Locker stores your clothing and Carrying Equipment; the Weapons
Cabinet stores extra weapons; the Ammo Box stores extra ammo in all calibres;
the Toolkit stores extra components; the Bookcase stores books and Illuminated
Manuscripts; and the Safe stores anything else (and is the only place where you
can swap Mission items out of your inventory if you need to store something you
don't need yet). All of these except the Safe have a limited capacity to start
off with, but can be upgraded at the store in Nuoland. When you craft something
at your home Workshop which you can't currently carry (or swap out something
you're carrying with something newly crafted) the unused item is placed
directly into storage.

In addition to Pack, there are five slots for Worn Items:
Shirt, Trousers, Jacket, Boots, and Head. Different kinds of Worn Items provide
distinct benefits, based on protection, style and carrying capacity. There are
also some full Sets of clothing, which function as uniform when worn and allow
you to be identified as a member of a specific faction or social group, even
letting you infiltrate otherwise hostile or unfriendly areas. Item properties
can include some special properties of varying level, such as the Waterproof
property, which significantly reduces the Stamina impact of rain or swimming,
or the Insulated property, which prevents electrical damage, or the
Fire-Retardant property, which significantly reduces burning damage.

There is no common form of currency on Pangyrea, so all
trading is based on commodities which people value.Food, drink, Components, Weapons, clothing,
worn items, Tools and different kinds of useable items can all be traded for.
You can also trade for cultural items, which can be more or less valuable
depending on condition and context; high-quality cultural items dating back to
the colonial fleet are most valuable, small tokens made by villagers the least.

Skills
Your Skills help you interact with the world. They govern
your proficiency with the different available weapon types, provide you with
the means to manipulate technology, and govern how you interact with other
people. You improve your Skills by earning XP through your actions and spending
that on improvements. You can also find Trainers in the world who will provide
you with a one-off increase in a specific Skill, in return for help with some
task or mission. There are 15 Skill in total, each representing a particular
approach to interacting with the world. As you increase your Skills, each has
Benchmark stages where you gain specific new abilities.

Hunter: using Simple Bows, Recurve Bows, Crossbows, Harpoon
Launchers and Spears, emphasising ability to move through the landscape without
leaving a trail and attack animals from stealth.

Athlete: your overall fitness and athletic ability,
advancing this Skill improves your Stamina and enables you to carry out special
moves such as sliding or leaping out of a sprint, climbing quickly, and rapidly
descending ropes and ladders, as well as increasing how long you can sustain
sprinting for, enabling you to be more agile while wearing armour, and
decreasing the Stamina damage you take when you dive into water from a
significant height.

Brawler: melee combat using your fists or primitive or
improvised weapons such as clubs, emphasising brutality and mobility.

Bladesman: using any kind of sword or dagger in melee
combat, emphasising precision and mobility

Technician: utilising technological items in the world and
using Workshops, including picking locks and disarming security devices

Scientist: your ability to glean information from tech in
the world

Doctor: how well you heal your wounds when using Medical
Kits, or heal others in need of aid

Charmer: your ability to persuade others to see your point
of view, or to offer to help you, with kind words and flattery, or create a
welcoming persona when disguised

Bully: your ability to intimidate or threaten other people
into doing what you want, or to create a domineering persona when in disguise

Trader: your ability to get better value out of trades, or
convince others to help you by offering something in return

Stamina, injuries, damage resistance and the environment

Unlike in other games, you don't have a 'health bar'. When
you take damage or encounter hazards in the world, this impacts first on your
Stamina. Your Stamina level also enables you to monitor how you're faring as
you explore, how hungry or thirsty you are, and whether you're in need of
sleep. As you travel, your Stamina will constantly deplete, very slowly, down
from green, to yellow, to blue. Strenuous exercise - sprinting, jumping,
fighting - depletes it quicker. When your slow back down, some of your Stamina
will regenerate, but the red area of the bar will not do so. To regenerate
this, you need to eat, drink and sleep.

Taking injuries also increase how much of your Stamina meter
stays red. When you're hit with a weapon, this depletes your Stamina to some
extent, but hard blows will also injure you. The Injury monitor in the HUD
shows which parts of your body are injured. Injuries effect you in different
ways depending on the location and severity; some will slightly disable you, reducing
your speed or accuracy, some will more seriously disable, and some will quickly
kill you. Your screen will start to blur red and your vision will swim if
you're badly injured and bleeding out, warning you that you need to carry out
first aid. To heal injuries, you need to use a Medical Kit or find a doctor,
and improving your Healing path in the CVA will enable you to heal quickly with
less intervention. Some damage (such as getting into a fist fight, or being hit
with a KO weapon) initially depletes your Stamina only, and only causes an
injury with sustained impacts.

Your damage resistance is based on seven categories of
potential trauma: Physical, Burning, Electrical, Chemical, Toxic, Radiological,
and Cold. Different kinds of trauma cause different injuries. Improving the CVA
and using different kinds of Worn Item improves your resistance to each of
these, to different extents and based on category. The better your damage
resistance, the longer it takes for you to be injured by trauma of the
appropriate category, and the less trauma of that category drains your Stamina.

Different hazards in the environment also cause different
types of trauma.

Travelling through bad weather (whether rain or severe heat)
in the world also drains your Stamina a little bit quicker than travelling in
temperate weather.

If your Stamina meter flashes blue, you are badly fatigued.
If you slow down, you can start to regenerate your Stamina, but trying to take
any strenuous action at this stage rapidly increases the red area of your
Stamina bar. Once your Stamina meter starts flashing red, you're in trouble,
and severe exhaustion will start to injure you. Eventually, you will pass out,
or worse, and need a jump-start from the CVA, leaving you vulnerable to fatal
trauma. If you manage to survive this, you'll wake up with a little bit of
Stamina, just enough to make it back to your home base to rest, recuperate and
heal up.